The “Neon Lights” crooner, who entered rehab in 2011 to seek treatment for an eating disorder and struggles with self-harm, tells Seventeen magazine that she still sometimes have bad days — and that’s apparently a good thing.

“Since I went to treatment, there have been days when it’s felt really easy, and I’ve felt great about where I am. But then I have moments when it’s not. That’s life,” she says. “You can’t just take your mind and your body into the shop and get it fixed. It doesn’t come out repaired. It’s not like a car. It takes time – pace yourself. Every day is a new opportunity to change your life and be who you want to be.”

“There are going to be times where you will have bad days, bad weeks and even sometimes bad months—but rainbows always come after the darkest storm,” she explains.

Demi Lovato on the cover of Seventeen’s August 2014 issue. [Seventeen/Ben Watts]

“I tell myself five things that I’m grateful for, for every negative thing that I think,” the singer says. “I like to have friends in my life who believe they’re going places and are working toward their dreams. When you’re growing and the people around you aren’t, that’s when you have to start shedding them. I’ve done that a lot over the past few years, but it has been so worth it, because the people in my life today inspire me to keep being creative, to have fun, and to be a good person.”